Fruticose Lichens

The pendent fruticose lichen called California Spanish moss (Ramalina menziesii) hanging from the branches of a valley oak (Quercus lobata) in the Coast Ranges of central California. Center photo shows the reticulate (netlike) pattern of the thalus of this lichen. Right photo shows several cup-shaped apothecia, proof that this epiphyte is indeed a lichen (lichenized fungus) and not a moss.

Ramalina leptocarpha. This is a pale yellowish-green fruticose lichen that commonly grows in pendulous tufts on oaks and conifers. It superficially resembles oak moss (Evernia prunastri), but lacks the whitish ventral surface of the latter species.

The Spanish moss that hangs from the branches of bald cypress trees (Taxodium distichum) in swamps of the southeastern United States is not a lichen or a moss. It is a flowering plant in the pineapple or bromeliad family (Bromeliaceae) named Tillandsia usneoides. The specific epithet usneoides means "usnea-like" referring to an epiphytic lichen namedUsnea (sometimes called "old mans's beard"). The right photo shows the small greenish flower of Tillandsia, proof that this epiphyte is indeed a flowering plant and not a lichen or moss.

Alectoria sarmentosa, a pendulous fruticose lichen that hangs in trees. It superficially resembles old man's beard (Usnea), but unlike Usnea it does not have a threadlike cord down the center of the thallus branches.

A basket of potpouri containing oak moss (Evernia prunastri), the same species collected in Europe for a delicate perfume. The basket is made from the interwoven leaves of Pandanus tectorius, a Polynesian native plant in the pandanus family (Pandanaceae).

Masonhalea richardsonii, a fruticose lichen native to the Brooks Range of northern Alaska. The generic name commemorates Mason E. Hale, famous lichenologist and author of Lichens of Califiornia.

Two species of fruticose ground lichens (Cladina evansii and C. subtenuis) in a sand pine woodland, Jonathan Dickinson State Park, southern Florida. From a distance, these striking lichens resemble clusters of white flowers growing along the trail. These uncommon lichens are protected in this beautiful state park, along with other rare and endangered species, such as the sand pine (Pinus clausa).

Iceland moss (Cetraria nivalis). Along with reindeer moss (Cladina rangiferina) this fruticose lichen carpets thousands of miles of North American and European tundra.

Cladonia chlorophaea, a common soil lichen on shady moss-covered banks and road cuts throughout the chaparral of coastal San Diego County. It is very similar and difficult to separate from another species C. fimbriata. Although the flattened thallus resembles a foliose lichen, it is technically a fruticose lichen because of the upright structures called podetia that resemble miniature golf tees. Inside the cuplike apex of each podetium are numerous soredia, appearing like granules in the right photo. Each soredium is a minute clump of fungal filaments intertwined with algal cells. It is an asexual reproductive structure that may disperse this species to new areas by the wind. Although many species of lichens produce powderlike soredia, Cladonia produces them on a podetium. The podetium is characteristic of several genera, including Cladonia, Cladina, Baeomyces and Pilophoron. In these genera, the podetium typically bears one or more spore-bearing apothecia at its tip. The podetium is truly a lichen structure that is not present in unlichenized fungi. The algal-fungal relationship in lichenized fungi clearly induces the gene activity necessary for the production of this structure. In another species of Cladonia called "British soldiers" (C. cristatella), the podetia are tipped with bright red apothecia.

Cladonia chlorophaea, a common soil lichen on shady, moss-covered banks and road cuts throughout the chaparral of coastal San Diego County. Although the flattened thallus resembles a foliose lichen, it is technically a fruticose lichen because of the upright structures called podetia that resemble miniature golf tees. The flowering plant is Jepsonia parryi, a native perennial that grows in shaded slopes among mosses, liverworts and lichens. The generic name commemorates Willis Linn Jepson, famous California botanist who wrote the original Manual of the Flowering Plants of California (1923).

Cladonia cryptochlorophaea, a fruticose lichen from the Brooks Range of northern Alaska. Cladonia species are classified as fruticose because of the upright structures called podetia that resemble miniature golf tees. The podetium is characteristic of several genera, including Cladonia, Cladina, Baeomyces and Pilophoron. In these genera, the podetium typically bears one or more spore-bearing apothecia at its tip. The podetium is truly a lichen structure that is not present in unlichenized fungi. In another species of Cladonia called "British soldiers" (C. cristatella), the podetia are tipped with bright red apothecia.

Cladonia ochrochlora , a common fruticose lichen on moist shady banks in the chaparral and coastal sage scrub of San Diego County. The upright potedia are unbranched and pointed. They are covered with farinose to granular soredia.

Close-up view of the podetia of Cladonia ochrochlora , a common fruticose lichen on moist shady banks in the chaparral and coastal sage scrub of San Diego County. The podetia are covered with mealy particles called soredia.

Pilophoron aciculare, a rock lichen in moist coniferous forests of northern California, Oregon and Washington. Like Cladonia this species produces slender, upright podetia, each tipped with a black apothecia.

British soldiers (Cladonia cristatella), a soil lichen with upright podetia bearing bright red apothecia at the tips. At the bottom of the centrifuge tube (left), the fungal component of this lichen (also named C. cristatella) has grown into a white, amorphous blob without its algal symbiont. In the right test tube, the algal symbiont (named Trebouxia erici) has grown into a mass of bright green cells. Only when these two symbionts form the "marriage" known as lichen is the unique structure of "British soldiers" formed. [Cultures courtesy of J.L. Platt, CSUSM, San Marcos, California.]

The dark fruticose lichen (Pseudephebe minuscula) on granite in the Sierra Nevada.